Co-Circulation of Phleboviruses and <i>Leishmania</i> Parasites in Sand Flies from a Single Site in Italy Monitored between 2017 and 2020

• Main Authors: Mattia Calzolari, Giuseppe Romeo, Emanuele Callegari, Paolo Bonilauri, Chiara Chiapponi, Elena Carra, Gianluca Rugna, Roberta Taddei, Davide Lelli, Michele Dottori
• Format: Article
• Language: English
• Published: MDPI AG 2021-08-01
• Series: Viruses
• Subjects: sand fly; <i>phlebotomus perfiliewi</i>; <i>phlebotomus perniciosus</i>; <i>leishmania infantum</i>; <i>phlebovirus</i>; toscana virus
• Online Access: https://www.mdpi.com/1999-4915/13/8/1660

Sand flies transmit <i>Leishmania infantum</i>, which is responsible for causing leishmaniasis, as well as many phleboviruses, including the human pathogenic Toscana virus. We screened sand flies collected from a single site between 2017 and 2020 for the presence of both phleboviruses and <i>Leishmania</i>. The sand flies were sampled with attractive carbon dioxide traps and CDC light traps between May and October. We collected more than 50,000 sand flies; 2826 were identified at the species level as <i>Phlebotomus perfiliewi</i> (98%) or <i>Phlebotomus perniciosus</i> (2%). A total of 16,789 sand flies were tested in 355 pools, and phleboviruses were found in 61 pools (6 Toscana virus positive pools, 2 Corfou virus positive pools, 42 Fermo virus positive pools, and 7 Ponticelli virus positive pools, and 4 unidentified phlebovirus positive pools). <i>Leishmania</i> was found in 75 pools and both microorganisms were detected in 16 pools. We isolated nine phleboviruses from another 2960 sand flies (five Ponticelli viruses and for Fermo viruses), not tested for <i>Leishmania</i>; the complete genome of a Fermo virus isolate was sequenced. The simultaneous detection in space and time of the Fermo virus and <i>L. infantum</i> is evidence that supports the co-circulation of both microorganisms in the same location and partial overlap of their cycles. A detailed characterization of the epidemiology of these microorganisms will support measures to limit their transmission.